THE INVESTIGATION into Boris Johnson’s comment piece for The Daily Telegraph has sparked fury among some Tory MPs who claim their party chairman, Brandon Lewis, is attempting to “kneecap” the former Foreign Secretary.

Theresa May has asked Mr Johnson - who in his column argued against a blanket burka ban - to apologise for his suggestion that muslim women who wear the burka looked like “letterboxes” and “bank robbers”.

A string of complaints have been lodged against Mr Johnson, but it remains to be seen if they have grounds because they depend on whether the now-backbencher’s statements broke the party code of conduct.

Mr Johnson, who resigned from the Government following Mrs May's Chequers proposals announcement, is refusing to apologise for his words despite the admission from the Tory Party it was now examining “numerous” complaints against him, prompting accusations of a witch hunt against the MP many have touted as a possible future leader.

A full investigation may be instigated to determine if Mr Johnson did indeed break the party’s code of conduct, which states Tory MPs and other holders of public office should “foster respect and tolerance” in their work.

Related articles

Potential sanctions could comprise removing the whip from Mr Johnson or suspending him from the Conservative Party for a period - although party sources have stressed this is unlikely.

The initial investigation into Mr Johnson spurred outrage from some Tory MPs who criticised Brandon Lewis, the party chairman, for rekindling the row earlier this week by demanding an apology from Mr Johnson.

One Tory MP said: “This is a complete own goal by Brandon Lewis. To anyone objective, it looks like a crude and unprincipled kneecap job on the favourite to succeed Theresa May.

“In the process he has managed to turn a minor story into a five-day frenzy of virtue signalling nonsense. Brandon needs to close this down or he won't last as party chairman.”

The complaints against Mr Johnson, which are currently being assessed by an “investigating officer”, may be dismissed it they are deemed “trivial”.

A Government source said: “Most complaints are not known about because people don't publicise them. This is not a choice that Brandon has made.”

Meanwhile, Conor Burns, Tory MP and backer of Mr Johnson, said: “It would be perverse and bizarre were the party to launch a formal investigation.

“When we have reached the stage when you cannot express an opinion it is a rum do in the party of freedom.

“What should have been a 24-hour news story has dragged on for the best part of a week and is damaging the party.”

Mrs May, calling on Mr Johnson to apologise, said his remarks had “clearly caused offence”.

But, defending the former Foreign Secretary, a source close to Mr Johnson revealed he wouldn’t be backing down, adding it was “ridiculous” to attack his comments.

“We must not fall into the trap of shutting down the debate on difficult issues," the source added.

Cressida Dick said Mr Johnson's remarks do not meet the threshold for a criminal offence (Image: GETTY)

“We have to call it out. If we fail to speak up for liberal values then we are simply yielding ground to reactionaries and extremists.”

Asked about Mr Johnson's remarks Metropoliitan Police Commissioner Cressida Dick did not express her personal opinion, but told a BBC Asian Network radio presenter: ‘I think everybody in public life has to think about the impact of what they say. Absolutely I am proud to police in a liberal democracy in which people have the right to express their opinion.

“What Mr Johnson said, if it is not criminal, is a matter for Mr Johnson his friends and colleagues and indeed the Conservative Party.”

Theresa May has asked Mr Johnson to apologise for the comments he made on women who wear the burka (Image: GETTY )

Background on the burka:

The burka - or burqa - is an enveloping outer garment worn by some women in Islamic traditions to cover themselves in public.